Today, owing to the development of electronic communication industries, portable terminals such as mobile communication terminals, electronic pocketbooks, Personal Digital Assistants (PDAs), and the like, are becoming necessities of modern society while becoming significant means for delivery of information that changes quickly.
As widely known, recent portable terminals apply a touch screen in which a screen touch induces an input. The touch screen is a screen equipped with an input device for, if there is a hand touch, receiving an input of its position. The touch screen satisfies users with its convenience. That is if a user hand touches character or picture information previously appearing on the touch screen, the portable terminal detects what item is selected by the user according to a touched position of the screen, and processes a command corresponding to the touch.
A portable terminal (hereinafter, referred to as a ‘touch screen terminal’) equipped with this touch screen provides a function of zooming in a screen. For one example, a user can zoom in a screen using a multi touch scheme. The multi touch scheme zooms in or out the screen depending on a change of a distance between points touched by user's two fingers. That is, if the user widens a space between the two fingers to increase a distance between two touch points, the screen is zoomed in and, if the user narrows the space between the two fingers to decrease the distance between the two touch points, the screen is zoomed out. Accordingly, to zoom in or out the screen up to a desired level, the user may have to repeat the aforementioned operation a number of times.